Computer systems employ data input, storage, processing and output integrated circuits. In order to assure proper operation of these circuits, they often need to be time-domain synchronized. In order to provide such synchronization, computer systems typically employ clock circuits for synchronizing the data transfer and process timing of these circuits. Synchronization of these circuits in modem high-performance and low-power computers requires several clock signals of varying frequency that themselves must be synchronized to one another. It is not a trivial undertaking to design such clock circuits that operate at multiple frequencies, with high-speed and with low power consumption.